aclocal_cc.m4: Remove use of implicit int from weak symbol checks

Implicit int is no longer part of the C language since the 1999
revision.

Submitted upstream: <https://github.com/pmodels/mpich/pull/6301>

diff --git a/confdb/aclocal_cc.m4 b/confdb/aclocal_cc.m4
index 36b44216d36dd8db..cafb5a6ae137f750 100644
--- a/confdb/aclocal_cc.m4
+++ b/confdb/aclocal_cc.m4
@@ -388,7 +388,7 @@ AC_CACHE_CHECK([for multiple weak symbol support], pac_cv_prog_c_multiple_weak_s
         #pragma weak PFoo_ = Foo
         #pragma weak pfoo_ = Foo
         int Foo(int);
-        int Foo(a) { return a; }
+        int Foo(int a) { return a; }
     ]])],[AC_LANG_SOURCE([[
         extern int PFoo(int), PFoo_(int), pfoo_(int);
         int main() {
diff --git a/modules/json-c/autoconf-archive/m4/aclocal_cc.m4 b/modules/json-c/autoconf-archive/m4/aclocal_cc.m4
index 8a1552d561306f24..cd28a4f937eaf824 100644
--- a/modules/json-c/autoconf-archive/m4/aclocal_cc.m4
+++ b/modules/json-c/autoconf-archive/m4/aclocal_cc.m4
@@ -383,7 +383,7 @@ extern int pfoo_(int);
 #pragma weak PFoo_ = Foo
 #pragma weak pfoo_ = Foo
 int Foo(int);
-int Foo(a) { return a; }
+int Foo(int a) { return a; }
     ])
 ],[
     AC_LANG_SOURCE([
diff --git a/modules/yaksa/m4/aclocal_cc.m4 b/modules/yaksa/m4/aclocal_cc.m4
index d15d6741602daf07..9fcf48527653ff01 100644
--- a/modules/yaksa/m4/aclocal_cc.m4
+++ b/modules/yaksa/m4/aclocal_cc.m4
@@ -422,7 +422,7 @@ extern int pfoo_(int);
 #pragma weak PFoo_ = Foo
 #pragma weak pfoo_ = Foo
 int Foo(int);
-int Foo(a) { return a; }
+int Foo(int a) { return a; }
     ])
 ],[
     AC_LANG_SOURCE([
diff --git a/src/mpi/romio/confdb/aclocal_cc.m4 b/src/mpi/romio/confdb/aclocal_cc.m4
index 36b44216d36dd8db..cafb5a6ae137f750 100644
--- a/src/mpi/romio/confdb/aclocal_cc.m4
+++ b/src/mpi/romio/confdb/aclocal_cc.m4
@@ -388,7 +388,7 @@ AC_CACHE_CHECK([for multiple weak symbol support], pac_cv_prog_c_multiple_weak_s
         #pragma weak PFoo_ = Foo
         #pragma weak pfoo_ = Foo
         int Foo(int);
-        int Foo(a) { return a; }
+        int Foo(int a) { return a; }
     ]])],[AC_LANG_SOURCE([[
         extern int PFoo(int), PFoo_(int), pfoo_(int);
         int main() {
diff --git a/src/mpi/romio/mpl/confdb/aclocal_cc.m4 b/src/mpi/romio/mpl/confdb/aclocal_cc.m4
index 36b44216d36dd8db..cafb5a6ae137f750 100644
--- a/src/mpi/romio/mpl/confdb/aclocal_cc.m4
+++ b/src/mpi/romio/mpl/confdb/aclocal_cc.m4
@@ -388,7 +388,7 @@ AC_CACHE_CHECK([for multiple weak symbol support], pac_cv_prog_c_multiple_weak_s
         #pragma weak PFoo_ = Foo
         #pragma weak pfoo_ = Foo
         int Foo(int);
-        int Foo(a) { return a; }
+        int Foo(int a) { return a; }
     ]])],[AC_LANG_SOURCE([[
         extern int PFoo(int), PFoo_(int), pfoo_(int);
         int main() {
diff --git a/src/mpl/confdb/aclocal_cc.m4 b/src/mpl/confdb/aclocal_cc.m4
index 36b44216d36dd8db..cafb5a6ae137f750 100644
--- a/src/mpl/confdb/aclocal_cc.m4
+++ b/src/mpl/confdb/aclocal_cc.m4
@@ -388,7 +388,7 @@ AC_CACHE_CHECK([for multiple weak symbol support], pac_cv_prog_c_multiple_weak_s
         #pragma weak PFoo_ = Foo
         #pragma weak pfoo_ = Foo
         int Foo(int);
-        int Foo(a) { return a; }
+        int Foo(int a) { return a; }
     ]])],[AC_LANG_SOURCE([[
         extern int PFoo(int), PFoo_(int), pfoo_(int);
         int main() {
diff --git a/src/pm/hydra/confdb/aclocal_cc.m4 b/src/pm/hydra/confdb/aclocal_cc.m4
index 36b44216d36dd8db..cafb5a6ae137f750 100644
--- a/src/pm/hydra/confdb/aclocal_cc.m4
+++ b/src/pm/hydra/confdb/aclocal_cc.m4
@@ -388,7 +388,7 @@ AC_CACHE_CHECK([for multiple weak symbol support], pac_cv_prog_c_multiple_weak_s
         #pragma weak PFoo_ = Foo
         #pragma weak pfoo_ = Foo
         int Foo(int);
-        int Foo(a) { return a; }
+        int Foo(int a) { return a; }
     ]])],[AC_LANG_SOURCE([[
         extern int PFoo(int), PFoo_(int), pfoo_(int);
         int main() {
diff --git a/src/pm/hydra/mpl/confdb/aclocal_cc.m4 b/src/pm/hydra/mpl/confdb/aclocal_cc.m4
index 36b44216d36dd8db..cafb5a6ae137f750 100644
--- a/src/pm/hydra/mpl/confdb/aclocal_cc.m4
+++ b/src/pm/hydra/mpl/confdb/aclocal_cc.m4
@@ -388,7 +388,7 @@ AC_CACHE_CHECK([for multiple weak symbol support], pac_cv_prog_c_multiple_weak_s
         #pragma weak PFoo_ = Foo
         #pragma weak pfoo_ = Foo
         int Foo(int);
-        int Foo(a) { return a; }
+        int Foo(int a) { return a; }
     ]])],[AC_LANG_SOURCE([[
         extern int PFoo(int), PFoo_(int), pfoo_(int);
         int main() {
diff --git a/src/pm/hydra2/confdb/aclocal_cc.m4 b/src/pm/hydra2/confdb/aclocal_cc.m4
index 36b44216d36dd8db..cafb5a6ae137f750 100644
--- a/src/pm/hydra2/confdb/aclocal_cc.m4
+++ b/src/pm/hydra2/confdb/aclocal_cc.m4
@@ -388,7 +388,7 @@ AC_CACHE_CHECK([for multiple weak symbol support], pac_cv_prog_c_multiple_weak_s
         #pragma weak PFoo_ = Foo
         #pragma weak pfoo_ = Foo
         int Foo(int);
-        int Foo(a) { return a; }
+        int Foo(int a) { return a; }
     ]])],[AC_LANG_SOURCE([[
         extern int PFoo(int), PFoo_(int), pfoo_(int);
         int main() {
diff --git a/src/pm/hydra2/mpl/confdb/aclocal_cc.m4 b/src/pm/hydra2/mpl/confdb/aclocal_cc.m4
index 36b44216d36dd8db..cafb5a6ae137f750 100644
--- a/src/pm/hydra2/mpl/confdb/aclocal_cc.m4
+++ b/src/pm/hydra2/mpl/confdb/aclocal_cc.m4
@@ -388,7 +388,7 @@ AC_CACHE_CHECK([for multiple weak symbol support], pac_cv_prog_c_multiple_weak_s
         #pragma weak PFoo_ = Foo
         #pragma weak pfoo_ = Foo
         int Foo(int);
-        int Foo(a) { return a; }
+        int Foo(int a) { return a; }
     ]])],[AC_LANG_SOURCE([[
         extern int PFoo(int), PFoo_(int), pfoo_(int);
         int main() {
diff --git a/test/mpi/confdb/aclocal_cc.m4 b/test/mpi/confdb/aclocal_cc.m4
index 36b44216d36dd8db..cafb5a6ae137f750 100644
--- a/test/mpi/confdb/aclocal_cc.m4
+++ b/test/mpi/confdb/aclocal_cc.m4
@@ -388,7 +388,7 @@ AC_CACHE_CHECK([for multiple weak symbol support], pac_cv_prog_c_multiple_weak_s
         #pragma weak PFoo_ = Foo
         #pragma weak pfoo_ = Foo
         int Foo(int);
-        int Foo(a) { return a; }
+        int Foo(int a) { return a; }
     ]])],[AC_LANG_SOURCE([[
         extern int PFoo(int), PFoo_(int), pfoo_(int);
         int main() {
diff --git a/test/mpi/dtpools/confdb/aclocal_cc.m4 b/test/mpi/dtpools/confdb/aclocal_cc.m4
index 36b44216d36dd8db..cafb5a6ae137f750 100644
--- a/test/mpi/dtpools/confdb/aclocal_cc.m4
+++ b/test/mpi/dtpools/confdb/aclocal_cc.m4
@@ -388,7 +388,7 @@ AC_CACHE_CHECK([for multiple weak symbol support], pac_cv_prog_c_multiple_weak_s
         #pragma weak PFoo_ = Foo
         #pragma weak pfoo_ = Foo
         int Foo(int);
-        int Foo(a) { return a; }
+        int Foo(int a) { return a; }
     ]])],[AC_LANG_SOURCE([[
         extern int PFoo(int), PFoo_(int), pfoo_(int);
         int main() {